Time switch



March 2, 1943. M. SCHLENKER 2,312,492

TIME SWITCH Filed July 20, 1940 3 Sheets-Sheet 1 Max jc/zeiz/er Patented Mar. 2, 1943 TIME SWITCH Max Schlenker, Peru, 111., assignor to General Time Instruments Corporation, New York, N. Y., a corporation of Delaware Application July 20, 1940, Serial No. 346,480

12 Claims.

This invention relates to time switches and in particular to time switches which automatically close a circuit at a predetermined time and thereafter open the circuit at a later predetermined time. Such time switches are particularly well adapted for use in connection with electric cooking devices such as ranges or roasters. The embodiment of this invention herein disclosed will be described with reference to its use as a range timer.

Various forms of switching mechanism are used in the range timers now commercially available. In a number of instances the switch mechanism takes up a considerable amount of space and is often housed in a separate compartment. Furthermore, the manufacture of such devices often calls for .parts, operation and equipment which I are not ordinarily used by a clock maker.

An object of this invention is to provide an improved time switch of such design that it may be readily manufactured by a clock maker.

A further object is to provide for an improved range timer a simple switch contacting means which may be mounted directly on the clock mechanism.

A further object is to provide an improved range timer in which all controls are mounted on the front face thereof and which is easy to operate.

A further object is to provide for an improved range timer contact mechanism which is positively and reliably controlled and which is so positioned with respect to the other parts of the device that no short circuits will take place.

A further object is to provide an improved range timer which can be set without inadvertently closing the circuit therethrough.

A further object is to provide an improved range timer which is adapted for occasional use and is provided with means whereby the clock mechanism may be readily wound and started.

Other objects, features and advantages of this invention will become apparent as the description proceeds.

In the drawings:

Fig. 1 is a reduced elevation of a preferred embodiment of this invention, the range timer being shown in its case, a portion of which is broken away;

Fig. 2 is a sectional elevation along line 2-2 of Fig. 3;

Fig. 3 is a plan view of the range timer shown in Fig. 1, the casing and clock dial being removed;

Fig. 4 is a section along line 4--4 of Fig. 3;

Fig. 5 is a detailed section along line 5-5 of Fig. 2;

Fig. 6 is a view similar to Fig. 3, which shows the parts in changed position, certain parts being broken away for purposes of clarity;

Fig. 7 is a view similar to Fig. 6 but showing the parts in a still different position;

Fig. 8 is a section along line 88 of Fig. 6; and

Fig. 9 is a section along line 9-9 of Fig. 7.

Referring now to the drawings, reference numeral IIJ indicates a casing which is provided with an opening in the face thereof through which a clock dial H is exposed. The front of the casing is provided with other openings through which the on shaft I2, the off shaft I3, the set-ting shaft I4 and the winding shaft I5 may extend, each of these shafts being provided with knobs I6, I'I, I8 and I9, respectively,

to facilitate the manual manipulation. The sleeve 20 surrounds the winding shaft I5 and terminates in a wheel 2I or other suitable means which may be readily grasped by the hand to start the clock, such starting means being hereinafter described in detail.

The dial is provided with the usual indicia thereon 'with which the hour hand 22 and the minute hand 23 cooperate. The dial II is also provided with two apertures, an on aperture 24 and an foff aperture 25 through which are visible indicia which appear on the rotatable on dial 26 and off dial I1, respectively. In Fig. 1 a portion of the casing is broken away to indicate the position of the on dial 26 in relation to the dial II and to other parts of the device.

The clock mechanism and the switching mechanism are mounted on or between the usual front and rear plates 39 and 3| which are spaced from each other by a plurality of spacers 32. The plates may be secured to the casing by suitable means not here shown.

The switching mechanism may be actuated by any suitable time-responsive driving means such as the usual spring driven clockwork, or by a synchronous electric clock motor. In the preferred embodiment herein shown spring driven clockwork is employed. Journaled in the front and rear plates is the usual main spring arbor 33 with which is associated the main spring 34, the outer end of which may be secured to one of the spacer members 32. A pinion 35 is staked to the arbor 33 and meshes with an idler pinion 36 mounted on a stub shaft 31. A pinion 38 on winding shaft I5 meshes with the idler pinion 36 so that the main spring may be wound by manually rotating the knob I9 in the usual manner.

The usual time train is associated with the the block H main spring and comprises a wheel 45 staked to the arbor 33 which meshes with a pinion M which is secured. 'to the minute wheel 42. Both the pinion 4| and the minute wheel 32 are frictionally associated with the minute shaft 53 by means of a spider 39 or other suitable mechanism as herein shown. The minute wheel it drives a pinion 44 which together with the Wheel 55 is mounted on the shaft 66. The wheel 45 meshes with a lantern pinion ll to drive the shaft 48 and the wheel 49 secured thereto. The latter wheel engages a similar pinion, not shown, to drive the escapement wheel 59 which is affixed to'a suit-- able shaft 5|. An escapement arm 52 is afiixed to a reciprocable shaft 53' and cooperates with the balance wheel 54 in the usual manner. The balance wheel is mounted on a stalf 56 and has associated therewith a hair spring 55. 7

As shown in Fig. 5 a plate 51 is mounted on the sleeve and is provided with a bent over arm 58 whichextends into a cutawayportion 59 of'the plate 3i]. A wiper 6B in theformofi a short length of steel wire extends inwardly from the plate 57 and is adapted to contact or wipe the periphery of the balance wheel 54. Aspring 61 is tensioned between lug B2 on plate 51 and lug 63 on front plate 30. It will be seen that the bent over arm 58 limits the rotation of the plate 5l-and sleeve 20'. The springfil biases the plate-assembly to a position wherein-the wiper is free-of the balance wheel. However; when it is wished to startthe clock after winding, manual rotation of the starting wheel 2! in the clockwise'direction asshown in Figs. 1 and 2 will cause the wiper to contact the balance wheel and give it sufficient kick to become operative. Range timers areoften affixed to the range and consequently such starting means is desirable inasmuch as the clockwork could not be shaken in order tostart the balance wheel in the usual manner.

Arsleeve 64-is rotatably'mounted on the minute shaft 43, to which sleeve the hour hand 22'may be secured. A wheel 65- is afiixed to the hour sleeve 64 and meshes with a pinion 61 rotatably mounted on stub shaft '66. The stub shaft may be suitably afiixed to the front plate and project forwardly therefrom. A pinion 69secured t the minute shaft 43 meshes with the wheel 68 which is secured to the-pinion 61 so that the wheel 65 and-the hour sleeve may be driven at the correct speed from the minute shaft.

A bracket H1 is suitably secured to the front plate by suitable means such as rivets. A block "H of insulating materialis secured to the bracket bymeans of screws 1-2. Resilient contact strips 14 and 15 are mounted one on each side of the insulating block '1! by means of screws 13 as shown in Figs. 3 and 4. The inner endsof the contact strips are provided with the usual contact points 16 and H, respectively, and the outer portions of each comprise aterminal lug 18- to which conductors (not shown herein) may be suitably secured. The terminal lugs may be connected across the heating element of an oven so thatthe circuit through the oven may be-closed when the contact points It and 17 are brought "together'by suitable means hereinafter described.

The insulating block H may be provided with one-or more projections 19 which-extend through corresponding apertures 80 in the base portion of the contact strips M and 15 which overlie I The screws-13- hold the contact strips closely againstthe faces of the blocks: so that the contact strips interlock with the; projeotions 19 thereby preventingthe contact strips 7-5 which extend laterally between the front and rear plates 30 and 3| from inadvertently being vertically displaced from their correct position. The contact strips are the only live parts in the complete assembly and if they are to be positioned between the plates it is essential that they be so mounted that they cannot possibly come in contact with any of the other metallic parts of the device.

It will be noted that in any position of the contact strips there is a considerable clearance between such strips and the plates or other metallic parts. This construction permits a great saving of space andavoids the necessity of placing the contact strips in a separate insulated compartment. The contact strips are sprung apart from one another so that they normally tend to assume a non-contacting position. They are adapted to be urged together by contact actuating members into contacting position against their resiliency.

Lugs 81 are formed on the rear plate 31, which lugs are bent over horizontally and extendinwardly to provide means for mounting contact actuating members 82 and 83, respectively. The contact actuating members are each rotatably secured to their respective lugs by means of a rivet 92, and a washer 93. may be interposed between each lug and contact actuating member to facilitate rotation of the contact actuating members.

The contact actuating member 82 has an arm of insulating material extending therefrom which is adapted to contact the contact strip 14 to urge the same inwardly against the bias orresiliency thereof to contacting position. Similarly the contact actuating member 83 is provided with an insulating arm 85 which serves to hold the contact strip 15 against the bias thereof in contacting position. A heavy coil spring .86is tensioned between .a lug 88 formed on contact actuating member 82 and a lug 90 on front plate 30, which coil spring biases the contact actuating member to its normal position, which corresponds to the off position as shown in Fig. 7. In this normal position of the contact actuating member the contact strip 74 is in its contacting position. A light coil spring 8! is tensioned between a lug 89 on the contact actuating member 83 and a lug 9| on the front plate 33 to bias the contact actuating member to its normal position, which corresponds to the "ofF position as shown in Fig. 7. In this normal position the contact actuating member permits the contact strip 15 to assume a non-contacting position.

An arm 94 is provided on contact actuating member 82 which cooperates with latching means to' hold the contact actuating member in displaced position in which the contact strip is permitted to assume its non-contacting position as shown in Fig. 3. Similarly an arm 95 which cooperates with suitable latching means is provided on contact actuating member 83 to hold the same in displaced position in which the contact strip 15 is maintained against the resiliency thereof in contacting position. The displaced positions of the contact actuating members are shown in Fig. '3 and correspond to the set position of the device as shown therein.

Arms 96 and 91 are provided for each of the contact actuating members 82 and 83, respectively, each arm being adapted for cooperation with means for manually displacing the contact actuating membersfrom their normal to their displaced positions.

Time responsive releasing means are provided to release the contact actuating members one after the other from the displaced position in which they are held by the latching means to cause first the circuit to be established through the contact strips and then to cause said circuit to be broken. Such latching and releasing means include shafts I and IOI which extend through both the front and rear plates and are journaled therein. Rotatably mounted on each shaft, forward of the front plate, are wheels I02 and I03 which are secured to hubs I04 and I05, respectively. The wheels and hubs are also adapted for axial movement with respect to their respective shafts. Each wheel I02 and I03 is provided with cams I06 and IN, respectively, formed by means of a lug which is stamped out of the wheel.

Discs I08 and I09 are each secured to the respective shafts I00 and IOI and each is formed with a cutaway portion to provide drop edges I I0 and III to cooperate with the cams I06 and I01. It will be noted in Fig. 2 that the discs are slightly undercut so that the drop edges thereof will project rearwardly. Furthermore, each disc is formed with a spiral periphery to provide a short radius at the point Where the respective cams I06, I01 first contact each disc thereby decreasing the frictional drag between each cam and disc and the power necessary to depress the respective wheels I02, I03, and to provide a longer radius at the drop edges III), II I in order to obtain greater accuracy. The rearwardly projecting drop edge permits better dropping action.

Heavy leaf springs H2 and H3 are secured at their lower extremities to the front plate 30 as shown in Fig. 2 and the upper end of each terminates in laterally extending portions I and I2I, respectively, which are apertured for shafts I00 and IOI, respectively, and which contact the hubs I04 and I05 to urge the wheels I02 and I03 and their cams I06 and I01 against the discs I08 and I09, respectively. Light leaf springs H4 and H5 are provided for each of the heavy leaf springs I I2 and H3 and each light spring is suitably secured at its lower portion to its corresponding heavy spring, as shown in Figs. 8 and 9. Headed pins H6 and H1 are mounted in the heavy leaf springs H2 and H3, respectively, each pin projecting through the corresponding light spring to serve as a guide for the latter. The upper ends of the light springs H4 and I I5 each terminate in bent over end portions which serve as latches H8 and H9 for cooperation with the arms 94 and 95, respectively.

Wheels I02 and I03 both mesh with pinion 61 and are driven thereby. Normally the wheel I02 i held spaced apart from the disc I08 by means of cam I06. In this position the heavy leaf spring H2 is urged by the hub I04 into contact with the plate 30. However, when the disc I02 is rotated by the clockwork into such position that the cam I06 drops off the drop edge I I0 the heavy,

leaf spring II2 will cause the wheel I02 to move forwardly or to the left as viewed in Fig. 8. At the same time the light leaf spring H4 is caused to move to the left to unlatch the contact actuating member 82, this position of the parts being shown in Fig. 8. Subsequent rotation of the wheel I02 with respect to the disc I03 will cause the heavy leaf spring II2 to move into the position shown in Fig. 9. However, the arm 04 after it is released does not swing entirely clear of the latch II3 due to the presence of lug I which extends upwardly from the upper edge of the front plate 30. Consequently the latch I I8 and the light leaf spring II4 are sprung outwardly from the heavy leaf spring IIZ. A similar lug I3I is provided to limit the motion of arm 95. The latching and releasing mechanism herein described is somewhat similar to that of the usual alarm release with the exception that the additional light leaf spring H4 is provided to permit the contact actuating member to remain in its normal position for any desired length of time; that is, until the apparatus is again set by causing the contact actuating member to again assume its displaced position.

Wheels I22 and I23 are provided with hubs I24 and I25, respectively, and each wheel and hub is afiixed to its corresponding shaft I00 and IOI. Spiders I26 and I2! or other suitable friction means are located between the hubs and the plate 3|, there being a substantial area of contact between each spider and its corresponding hub to hold the shafts I00 and IOI in a predetermined position and to overcome any tendency of the cams I06 and ID! to drag the discs I08 and I09, respectively. A pinion I20 is secured to the rear end of the on shaft I2, which pinion meshes with wheel I22 whereby the dial 26 and the disc I08 may be set to any desired position. A similar pinion I20 is secured to the off shaft I3.

The setting shaft I4 is journaled in lugs I32 and I33 which project upwardly from the edge of the front and rear plates, respectively. A pinion I34 is secured to the setting shaft and meshes with the wheel 60 whereby the hour and minute hands may be set. The frictional association between the minute wheel 42 and the minute shaft 43 permits the setting of the clock hands. At the same time the rotation of the pinion 6'! cause the wheels I02 and I03 and their respective cams I06 and I0! to be set to the desired position for proper release of the latching means.

The setting shaft I4 is also mounted for axial movement and at its rear end is provided with a disc I35 which engages the arms 96 and 91. A compression coil spring I36 surrounds a portion of the setting shaft I4 and is confined between lug I33 and a collar I3'I to bias the setting shaft forwardly. Consequently when the contact actuating members have been manually set in their latched or displaced position by means of a pull on the setting shaft I4 the setting shaft will extend outwardly and indicate to the operator that the range timer is in the set position as shown in Fig. 3. After either or both of the contact actuating members have been released the setting shaft is urged rearwardly and the position of the knob indicates to the operator that the device is no longer set. The pinion I34 is of sufiicient width so that it will always remain in mesh with the wheel 68 whether the set shaft I 4 is in the set position or not. As indicated in Fig. 3, the latch H8 is somewhat closer to the central plane of the apparatus than the latch H9. Cons quently when the setting shaft is withdrawn the contact actuating member 82 will be latched prior to the latching of contact actuating member 83. By this construction the contacts will not be inadvertently closed during the setting operation.

As shown in Fig. 1, the'range timer is set to go on at 2 oclock and off at 3 oclock. The position of the parts is shown in Fig. 3 wherein the spring contact strip I5 is held in its contacting position by means of the displaced conactactuatina nemberi 83 and-the. contac st p t; iszpermitted. to: ass. 3e'its.;n a no -c ntactingpositionby Virtue of the displaced position of contact, actuating; member 82. At 2 oclocl; the cam; I06, which is rotated by the clockwork, drops offthe drop, edge H0 thereby permitting the heavy. spring I I2 and the latch H8, to move forwardly and release the contact actuating member 82, The spring 86 is stronger than the natural bias; of the contact strip M and it causes the contact strip 14 to be moved inwardly to its contacting position wherein the contact points I6 and]? are in contact with each other and the circuit is closed through the heatingelement. This position of the parts is shown in Fig. 6 and may be termed the on position.

At 3 oclock theclocl work will have moved the cam I01 to a position where it drops off the drop-edge Hi thereby permittingthe heavy leaf spring H3 and-thelatch H9 to move forwardly and release the contactv actuating member 83.

The contact strip 15 is thenpermitted to spring backwardly out of contacting position into its normal non-contacting position thereby opening the circuit through the contact strips and through the heating element. This position or the "ofi position of the parts is shown in Fig, 7.

The parts may, at any time thereafter, be changed to the set-positio n shown in Fig. 3 in which the contactactuatingmembers 82 and 33 are latched in their displaced position ready for subsequent release. The time of such subsequent release may be readily. predetermined by rotating the knobs- I6 and ILto the proper position'as indicatedbytherotatable dials 26 and 21.

If the range timer'is not used every day the main spring will becomeunwound. Upon winding the main spring. and setting the clock the balance wheel may be started by manually rotating the wheel 2| through a. portion of a revolution.

While there havebeen shown and described certainembodimfints of the invention, it is to be understood thatv it is capable of many modifications. Changes, therefore, may be made without departing from the 5. .01 6 of the invention as, describedin the appended claims, in which it is the intention to.claim all novelty inherent inthe invention a broadly as possible, in view of the prior art.

I claim:

1. A time switch comprising tWo spaced parallel plates, time responsive meansmounted on said plates, resilient electric contact members mountedonsaid platesand insulated therefrom and being normally spaced from each other. in set and oif positions, and contacting each other in on position, spring biased means adapted to be released from displaced positions by said time responsive means to cause said contact members to successively assume on and oifpositions at predetermined times and a single manually actuated means engaging said spring-biased means for restoring the same from off to set position without changing the relative position of said contact members.

2. A time switch comprising two spaced parallel plates, time responsive means mounted on said plates, resilient, electric contact members mounted on saidplates and insulated therefrom and being normally spaced-from each other in set and off positions, and contacting each other in onposition, a contact actuating member for. eachof-said contact members to control the positions thereof, means for biasing each of said contact actuating members into ofi position, common means for manually displacing both of said contact actuating members to set position, means for maintaining said contact actuating members in set position, and releasing means controlled by said time responsive means for releasing said contact actuating members individually at predetermined times to cause said contact members to assume first on and then off positions.

3. A time switch comprising a contact member, an actuating member for actuating the same, a latching member for maintaining said actuating member in displaced position, axially displaceable rotatable cam means, time responsive driving means for said cam and adapted to cause axial displacement thereof at a predetermined time, a resilient arm confined by said cam means and associated with said latching member to cause the same to move from latching to'unlatching position with said resilient arm at said predetermined time and capable of being restored to confined position independently of said latching member, and manually actuated means for displacing said actuating member and permitting restoration of said latching member to latching position.

4. A time switch comprising a contact member, an actuating member mounted for limited displacement for actuating the same, a resiliently mounted latching member for engaging a portion of said actuating member to maintain said actuating member in displaced position, axially displaceable rotatable cam means, time responsive driving means for said cam and adapted to permit axial displacement thereof at a predetermined time, and a resilient arm confined by said means and urging the same into displaced position, said latching member being mounted on said resilient arm to be moved thereby from latching to unlatching position with said resilient arm at said predetermined time to release said actuating member from displaced position into a position wherein said actuating member maintains said latching member in unlatched position during and after the time that said cam means causes restoration of said resilient arm to confined position.

5. A time switch comprising a timing mechanism, cam operated releasing mechanism controlled thereby, a contact actuating member, a latch cooperating with said contact actuating member in interlocking relationship to maintain the same in displaced position before operation of said cam operated releasing mechanism, and to be maintained in inoperative position by said contact actuating member after said operation, said latch being associated with said releasing mechanism for positive control of said interlocking relationship in one direction only, manually actuated means for positive control of said interlocking relationship in the other direction, and contact means actuated by said contact actuating member.

6. A time switch comprising a timing mechanism, a contact actuating member, a latch cooperating with said contact actuating member in interlocking relationship to maintain the same in displaced position, a latch releasing member, and cam means controlled by said timing mechanism and confining said latch releasing member for controlling the operation of said latch releasing member and the release of said latch, said latch being resiliently mounted onv said latch releasing member to permit restoration of said latch to latching position after restoration of said latch releasing member to confined position and independently thereof.

7. A time switch comprising a timing mechanism, contact means, an actuating member for said contact means adapted to be latched in a displaced osition, a periodically oscillating member driven by said timing mechanism, latch means associated with said periodically oscillating means in such a manner as to be actuated thereby only to effect release of said actuating member, and being independent thereof after such release until said actuating member is again set in displaced position.

8. A time switch comprising a timing mechanism, two individually movable contact members, an actuating member for each contact member, means biasing said actuating members to off" position, latching means to maintain said actuating members in set position, in each of which positions, said contact members are separated from each other, means actuated by said timing mechanism for releasing said actuating members from displaced position in a predetermined order at predetermined times whereby said contact members are operated to establish and break a circuit therethrough, and common setting means to displace said actuating members and to cause the same to be latched in displaced position in the same order in which they are released whereby inadvertent release of said common setting means after only one of said actuating members are latched will prevent the establishment of a circuit through said contact members.

9. A time switch comprising two spaced parallel plates, a time train mounted on said plates, resilient contact members mounted between said plates, contact actuating members, separate means controlled by said time train to release said contact actuating members from a set position to an off position at predetermined times to cause operation of said contact members, a setting shaft rotatably mounted in said plates for axial movement and engaging said contact actuating members for restoring same from off position to set position, and a pinion secured to said shaft and engaging said time train for setting said time train.

10. A time switch comprising two spaced parallel plates, a time train mounted on said plates, resilient contact members mounted between said plates, contact actuating members, separate means controlled by said time train to release said contact actuating members from a set position to an off position at predetermined times to cause operation of said contact members, and a setting shaft rotatably mounted in said plates for axial movement and engaging said contact actuating members for restoring same from off position to set position, said shaft being associated with said contact actuating members so that one axial position thereof indicates that both contact actuating members are in said set position and that the apparatus is conditioned for a complete cycle of operations, and so that another axial position thereof indicates that at least one of said contact actuating members is in said off position.

11. A time switch comprising two spaced parallel plates, a time train mounted on said plates, resilient contact members mounted between said plates, contact actuating members, separate means controlled by said time train to release said contact actuating members from a set position to an off position at predetermined times to cause operation of said contact members, a setting shaft rotatably mounted in said plates for axial movement and engaging said contact actuating members for restoring same from off position to set position, said shaft being capable of assuming one of two extreme axial positions, means for biasing said shaft into that one of said two extreme axial positions which corresponds to the set position of both of said contact actuating members to indicate such condition to the operator, and a pinion secured to said shaft and meshing with a portion of said time train for setting the clock hands thereof, said pinion being of a width greater than the length of the axial movement of said shaft whereby said pinion meshes with said time train in either of said extreme axial positions.

12. Releasing means for a time switch comprising a cut away disc, a rotatable cam in axially displaceable operative relationship thereto, and a timing mechanism for causing relative rotation of said disc and cam, said disc being provided with a spiral periphery and a radial drop edge, and said drop edge extending into the cut away portion of said disc and being disposed at a greater distance from the center of said disc than that portion of said disc which initially contacts said cam.

MAX SCHLENKER. 

